Planooraph co



u iTED sT rns r rENT onnion.

GEORGE LEONARD MCALPINEQJoF cATroRn, ENGLAND, AssIGNoR To JoiiN LGRIFFIN- a soNs, LIMITED, or LONDON, EN LAND.

FIRING MEcHAN'I'sMoaFUsn r03 ExrLosIvE BODIES.

Specification of Let ters Patent. I Patentedsp tl 16,1919,

Applicationfiled Apri1'22, 1918. Serial No. 230,049;

To all whom may concern. a Be it known that I, GEORGE'LEONARD M0- ALPINE, a subject of the King of 'Great Britain, residing at 34-Inchmery road, Catford, in the county of Kent, England,have invented certain new and useful Improvementsin or Relating to Firing Mechanism or Fuses-for Explosive Bodies, of which the following is a specification.

This invention relates to delay action fir- "ing mechanism or fuses for shells, bombs,

-- means of a soluble member that is placed at the time of setting under the action of a suitable solvent which slowly acts upon the said member so that at aboutthe end of the predetermined interval the member yields 1 to the mechanical pressure of thefiring pin or other firing mechanism which isxthereupon released and fires the explosive charge. A suitable soluble member is found-tobe 'a disk or diaphragm of celluloid or like cellulose compound (for example cellulose acetate) that is. acted upon by an organic solvent, such as acetone or amyl-acetate, the effect of which is gradually toipenetrate the celluloid, which absorbs the solvent and weakens until its resistanceis insufiiclentto hold up the firing mechanism. This action 40 "one in whichthe solvent. material is actually is much steadier thanan ordinary solvent dissolved away from the surface,the.rate of solution in this casejdepending on the concentration of the liquid at thersurface and therefore varying if the liquid flows.

A. convenient construction embodying "my invention comprises a firingpin having a coned or sloping surface meeting the end of a retaining pin or catch-the head of which abuts against. the soluble disk or. diaphragm, the latter being secured 111 a solvent chamber by a smallscrewed ring or tubular plug, preferably with a protecting washer between it and the diaphragm. When the fuse is to beseta ismallflquantlty of the solvent is introduced into the said chamber,

which is then closed'byascrew' or other cover or plug. Or the solution maybe introduced in a small'contai'ner arranged to-be pierced or otherwise opened on discharge or impact of the shell. When the solvent action has proceeded until the disk is sulficiently weakened the firing pin under its spring pressureis able to push back the retaining pm by the wedge action of the conical or sloping'surfac'e, when thefirin'g pin is released and strikes a detonato'r by means of whichthe charge is fired. I p

In order that the said'inve'i'itio'nmay be clearly understood and readily carried into veft'ect,.I will describe the same more fully with reference to the accompanying 1draw- V ings, in which Figures 1 to i show in section four shell noses'illust'rating four modifications 0f the device; and Y Fig. 5 is a longitudinal section of a delay action fuse applied to a game tube.

A is the shell nose. B is the firing pin with the spring I). O is the retaining pin or catch. D is the solubleme mber in the form of a diaphragm or disk. E is the chamber receiving the solvent and closed at "one end by the disk D.

Referring to the device shown inliig'l the firing pin'B and the retaining pin C' are placed at right angles to each other, the

'. former beingmade with a sleeve shank fitting over alongitudinalguiding pin 1) which is screwed in the tip-a of the shell. nose, the tip orcap'screwing on the end of the nose and'allowing of access'to the chambera in which the firing-pinis placed.

The chamber receiving the solvent is formed laterally in the-nose A and is closed by the screw plug c which bears upon the retaining ring 0, which is separately screwed into the chamber and secures the soluble disk D in the inner end of the chamber. The head '0 of the retaining pin O rests against the-"disk and the inner-end-of the pin projects forwardly into the chamber a under the conical head 6 of the firing pin.

The operation of the device is as follows :When the chamber E is filled with the acetone or other solvent and-the chamher is again closed by inserting the plug 6, i

penetrating the disk until, after aninterval back the retaining pin C, releasing the firing pin which immediately springs forward and strikes the detonator cap carried by the holder 64 secured in the base of the shell nose.

In the modification illustrated in Fig. 2 the principle of operation is the same, but the firing pin B is placed in the lateral chamber a and the solvent chamber E is longitudinal and immediately under the tip Or cap a, which serves in place of the plug a in the first construction. The retaining pin. C is longitudinal and the soluble disk D lies in the base of the chamber E, the retaining ring 6 h oldin the disk in place through the small steel washer or friction ring 6 which prevents abrasion of the disk on screwing up the ring 6.

The construction of the firing pin is similar to that shown in Fig. 1, but the guiding pin 6 is lateral instead of horizontal and is screwed in the plug a closing the end of the chamber a at the opposite end of which is fitted the cap a communicating with the detonator a through the small flash passage a. The general operation of the device is as already described in connection with Fig. 1.

I11 the modification shown in Fig. 8, the fuse is arranged to be cocked on discharge and for this purpose the firing pin spring Z) is normally unenergized and is energized on discharge by the inertia member F which takes the place of the fixed guidingpin b in the previous construction. This inertia member slides in the chamber a in the tip or cap a and is provided with a guide sleeve extension f receiving the stem 6 of the firing pin B. The general construction of the fuse is similar to that shown in Fig. l, the firing pin being longitudinal and the retaining pin lateral. The operation of the device is as follows:-On discharging the shell the set-back of the inertia. member F-compresses the firing pin spring 6, the pin itself being held by the retaining pin I On compres sion occurring the two small catch pins f of the inertia member are caused to'project outward by the spring f as soon as the inertia member reaches such a point that the pins can project into the annular recess a at the base of the chamber'a The firing pin is then held in energized position and firing can occur as soon as the soluble disk D is sufficiently weakened by the solution to release the firing pin.

In Fig. 4 a construction is shown which prevents cocking of the fuse before percus-' ..:-form ofa,v separate head.

to the gaine tube of a shell.

arranged to operate in opposite direction to on discharge. The firing pin spring is retained between the -head of the inertia member F and the end of the recess a in the nose tip a, the inertia member projecting into the firing pin, which is made in the To prevent any danger of the firing pin being released on discharge a safety pin G is provided which extends under the sloping face of the firing pin opposite to the retaining pin C, the

safety'pin beingheld by the small catch rod 9, the upper end of which meets the Hat spring g which may form a segment of a circle. The safety pin G is held by its catch until percussion of the shell, which causes the rod 9 to move forward against the spring 9 and release the safety pin.

On percussion of the shell the inertia member F energizes the spring I) and moves forward against the force of the spring until the small catch pins. f engage behind the end of the firing pin 13, which is retained by a shoulder in its cavity or recess so that forward movement is prevented. The device is now cocked and on weakening of the soluble disk D the firing pin pushes back both the retaining pin C and the already freed safety pin G and strikes the detonator cap.

Cooking devices such as are described in connection with Figs. 3 and 4imay be ar ranged to admit the solvent to the soluble diaphragm on discharge or percussion of the shell; for example, by piercing a container in which the solvent is introduced, so that the. timing of the fuse is from discharge or percussion. This action may be in addition .to or substitutionof the spring energizing operation.

'In Fig 5 the device is shown as applied In this case the firing pin B is placed to the gaine tube I-I so as to slide longitudinally therein, the firing pin spring 7) being compressed between a flange 5 at the end of the pin B and a shoulder it inside the tube. The outer end of the firing pin B is made with an inverted cone surface 6 meeting thetwo opposite retaining pins C. The solvent may be placed .in an annular channel h formed by a sleeve 7& screwing on the head of the gaine tube and removed for fitting the soluble diaphragms D and retainin pins G which are securedby the small was her k and tubular screwed plug 7L through which the solvent reaches the back of the diaphragm. The

head of the gaine tube can be closed, after admission of the solution, by a cap screwing on the aforesaid sleeve 7L The delay action has been shown as applied to shells but it is equally applicable to bombs, mines 'and other explosive bodies without substantial alteration.

What I claim and desire to secure by Letters Patent of the United States is 1. In firing mechanism for explosive bodies, a spring operated firing device, a catch adapted to hold up the said device, a diaphragm of cellulose compound such as celluloid against one face of which the catch abuts, for holding up purposes, and means for admitting a slowly acting organic solvent to the other face of said diaphragm, for the purpose specified.

2. In firing mechanism for explosive bodies, a spring operated firing device, a catch adapted to hold up the said device, a diaphragm of cellulose compound against one face of which the catch abuts, for holding up purposes and means for admitting acetone to the other side of the said diaphragm, for the purpose specified.

8. In firing mechanism for shells, a spring operated firing device, a soluble retaining member for the said firing device, means for admitting a slowly acting solvent to the said member and means by which the firing device is cocked upon sudden acceleration of the shell on discharge or impact.

4. In firing mechanism for shells, a spring operated firing device, a soluble retaining member for the said firing device, means for admitting a slowly actin solvent to the said member and an inertia evice by which the firing device is energized upon sudden acceleration of the shell on dlscharge or impact.

5. In firing mechanism for shells, a'spring operated firing pin of which the spring is normally unenergized, an inertia device adapted to energize the spring upon sudden acceleration of the shell, a catch adapted to hold up the firing pin against the pressure of the energized spring, a soluble diaphragm holding the catch in operative position and means for admitting a slowly acting solvent to the said diaphragm.

6. In firing mechanism for shells, a spring operated firing pin of which the spring is normally unenergized, an inertia member adapted to energize the spring upon sudden acceleration of the shell, a catch holding the spring in energized condition, another catch holding up the firing pin against the pressure of the energized spring, a soluble diaphragm holding the second catch in operative position and means for admitting a slowly acting solvent to the said diaphragm.

7. In firing mechanism for shells, a gaine tube, aspring operated firing pin fitted in the said gaine tube, a catch adapted to hold up the firing pin, a soluble diaphragm against one side of which the catch bears for holding the catch in operative position and a chamber provided in the game tube at the other side of the diaphragm adapted to be supplied with a slowly acting solvent, which acts upon the said diaphragm, for the purpose specified.

GEORGE LEONARD MoALPINE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). G. 

